Deepika Pawar et al, / (IJCSIT) International Journal …

1 ASMF: Attribute Signature Management Framework for Digital Document Security and Integrity Deepika Pawar , Prof. Mahendra K. Verma Department of Computer Science & Engineering Sushila Devi Bansal College of Technology, Indore ( ) -453331, India Abstract Data security and protection is the major factor towards gaining the complete control over the system. It deals with the necessary factors required to offer the robust protection levels towards accessing the authorized data. Authentication and cryptosystems are few of such approaches which deal with user s identity verification and data confidentiality. When the identity and correctness of data travelling through open medium is demanded then hashing is applied due to its one way property.

2 It detects the unauthorized changes and modification performed during transmissions. Well known implementation area of hashing is digital signatures which deal with the documents originality and creators identity. It is modified with adding additional information related to the attributes of users and comes under attribute based signatures (ABS). We have made in depth analysis of some previous approaches offering the ABS phenomenon and found some of the unsolved issues solution to which reduces the complexity, consumption and overhead associated with signature generations and verification.

3 This paper proposes a novel attribute signature management framework (ASMF) for handling the process of digital signatures with attributes and its predicate logic. The solution contains the versatile primitives to allow the signing parties having complete controls over the signature generation and the fine grained access security controls. It has a predicate logic attested with message and hides the signatures privacy. After analyzing the approach analytically some of the benefits were found which can be further verified by the implementation solution over the suggested framework in near future.

4 Keywords Data Security, Digital Signature, RSA, MD5, Certificate , Attribute Signature Management Framework (ASMF), Computational Complexity, Resource Consumption, Overhead; I. INTRODUCTION Cryptosystem deals with data security and protection which were designed in temporary fashion where the attacked systems are handled. All the developed models are mathematical strong to handle the unauthorized access and changes tried by the attackers. This mathematical problem is computational hard and the complexity of system needs to be assumed which was in traceable and used as a major building block for security system.

5 Cryptosystems are further pared into symmetric and asymmetric nature depends on the key used. Some of the examples of such cryptosystems are DES, AES and RSA. Here the RSA approach is a public key cryptosystem. The tools developed with these cryptosystems are offering through random oracles for proving the security of a scheme. A random oracle is an oracle that when queried responds with a random reply, subject to the condition that the reply is different for various queries but the same when the same input is queried again. Such an oracle has the desired properties such as preimage resistance and collision resistance.

6 Signatures have existed as a means of authentication for ages. It takes different formats according to the application. Until that point signing a document meant identifying the person. Signatures have been very useful in creating certified documents, but it has generally been necessary to rely on external evidence that the persons signing the document are qualified to do so. This is today's challenge. In the early days of digital signatures, signers owned a pair of keys, a public key known to everyone used as an input for the verification process and a private key known by the signer and used in the signature process.

7 Then the scheme is proved secure under that random oracle assumption. Finally when it comes to actually implementing the scheme the random oracle is replaced with a strong hash function. Researchers believe that proving a cryptosystem secure under the random oracle is equivalent to proving the security of the scheme dependent on exploiting the hash function used. Research in Attribute based signatures followed a certain trend. Cryptographers would identify an application that requires attribute signatures where that application would require certain properties that no existing cryptosystem provides.

8 They would propose a totally new scheme with new security notions that serve such properties. The result was several schemes each serving a very specific application making it hard to employ in any other. The following are two examples of such schemes: (i) Anonymous Credentials: Such systems have users and organizations. Organizations know the users by their pseudonyms and they issue credentials to these pseudonyms. Users, anonymously, can prove possession of a credential even to organizations that know them with a different pseudonym while unforgeability of credentials is guaranteed.

9 (ii) Attribute based signatures: A system that is very similar in concept with anonymous credentials, however, it can mix more than one attribute in one query ( signature). Designing a scheme for a specific purpose lead to overlooking common problems. One of the most challenging problems is revocation and finding a standard infrastructure. Deepika Pawar et al, / (IJCSIT) International Journal of Computer Science and Information Technologies, Vol. 7 (2) , 2016, Digital Signature If a user wants to send a signed document to another user, public key is used to identify the users and it was known to everyone and the secret key is not known.

10 Using the secret key and a message, first user can create a signature and send it to another. The recipient user can verify the signature using the message and the public key. The signature contains several elements that look random to recipient. Among these elements is one which is referred to as a Fingerprint . Second user (Recipient) knows the verifying procedure which will enable him to make use of the public key and the signature in order to recalculate the Fingerprint . If what he calculated is equivalent to what he got from first user (Sender) then accept signature otherwise reject it. A Digital Signature Scheme is a set of algorithms.